public class Algebra

{
   
public static void main(String[] args)

{

      
System.out.println("Given: f(x) = 3x - 15");
      
System.out.println("Let x = 4");
      
System.out.println("Then");
      
System.out.println("  f(4) = 3x4 - 15");
      
System.out.println("       = 12 - 15");
      
System.out.println("       = -3");
  
}

}